It is established that special number calls, such as by way of example and not by way of limitation emergency service calls, may best be serviced by routing such calls to an answering point assigned to handle situations involving such calls within a geographic responsibility area that includes the geographic location area of the calling unit placing the call. Geographic location area of a calling unit may be ascertained on more than one occasion using different technologies or under different conditions so that later-determined locations may be more accurate than earlier-determined locations.
It is also established that special number calls should be routed to an answering point as soon as possible so that desired service or other response may be carried out as soon as possible. This speed of response is especially important in connection with emergency service calls. Some calls such as emergency service calls may be best taken or received as soon as possible by an answering point that may be close to the calling unit, though not necessarily assigned to render aid to the geographic area in which the calling unit is operating. This may be so for example, to assure that at least some notification of the reported emergency may be received somewhere in the emergency communication system as early as possible in case the emergency service call may be interrupted.
By way of example and not by way of limitation, if a first determination of location of a calling unit is determined only to an accuracy that the ascertained geographic location area for the calling unit is covered by geographic responsibility areas of more than one Public Safety Answering Point (PSAP; sometimes referred to as a Public Safety Answering Position) it may be advantageous to concurrently route the call to more than one PSAP so as to ensure that at least one answering point in the emergency service system receives information in connection with the call before the call may be disconnected or otherwise lost. If a later determination of geographic location of a calling unit is more accurate than an earlier-determined position, the number of receiving answering points may be reduced. If a later determination of geographic location of a calling unit is sufficiently accurate, the number of receiving answering points may be changed to assure that only the one answering point having a geographic responsibility area including the geographical location area of the calling unit may be communicatively coupled with the calling unit.
Examples of special number calls include 9-1-1 calls for seeking emergency services and other abbreviated number calls for non-emergency special services, such as “N-1-1” systems. Examples of such N-1-1 systems include “3-1-1” (urgent but not emergency calls) and “5-1-1” (traffic inquiry calls). Special number calls may also include, by way of further example and not by way of limitation, abbreviated numbers for calling commercial services, such as “*820” (calling a radio station) or “GOTIX” (calling for tickets).
For purposes of illustration, by way of example and not by way of limitation, the present invention will be described in the context of an emergency service network in the United States, commonly referred to as a 9-1-1 network. The teachings of the present invention are equally applicable, useful and novel in other special number calling systems, such as maintenance service networks, college campus security networks, abbreviated number networks for calling commercial services and other networks.
There is a need for a system and method for concurrently routing special number calls from a calling unit to at least two answering points having geographic responsibility area at least partly in common with geographic location area of the calling unit.